CDCP Structured Cabling and Standards 4 — Questions and Answers
Question 1: What is the maximum pulling tension allowed for a 4-pair UTP cable during installation?
- 25 lbf (110 N) (Correct answer)
- 50 lbf (220 N)
- 75 lbf (333 N)
- 110 lbf (489 N)
Correct answer: 25 lbf (110 N)
ANSI/TIA-568 specifies a maximum pulling tension of 25 lbf (110 N) for 4-pair UTP horizontal cable to prevent stretching the conductors or damaging the twist geometry.
Question 2: In a data centre, what does the term 'alien crosstalk' (AXT) refer to?
- Signal interference between adjacent cables in a bundle (Correct answer)
- Crosstalk within a single twisted-pair cable
- Interference from external electromagnetic sources
- Signal reflection at connector terminations
Correct answer: Signal interference between adjacent cables in a bundle
Alien crosstalk (AXT) is electromagnetic interference between signal pairs in adjacent but separate cables, which becomes a significant concern in high-density data centre cabling.
Question 3: Which ANSI/TIA standard specifically addresses data centre telecommunications infrastructure?
- ANSI/TIA-942 (Correct answer)
- ANSI/TIA-568
- ANSI/TIA-606
- ANSI/TIA-569
Correct answer: ANSI/TIA-942
ANSI/TIA-942 'Telecommunications Infrastructure Standard for Data Centers' defines requirements for data centre cabling topology, pathways, and spaces.
Question 4: What minimum bend radius must be maintained for a Category 6A UTP cable during installation?
- 4 times the cable diameter
- 8 times the cable diameter (Correct answer)
- 10 times the cable diameter
- 1 times the cable diameter
Correct answer: 8 times the cable diameter
ANSI/TIA-568 requires a minimum bend radius of 8 times the cable outer diameter for Cat 6A UTP during installation to preserve signal integrity.
Question 5: What is the purpose of the Equipment Distribution Area (EDA) in TIA-942 data centre cabling architecture?
- Houses end-user equipment such as servers and storage devices (Correct answer)
- Provides cross-connection between horizontal and backbone cabling
- Serves as the main distribution point for the entire data centre
- Connects the data centre to the campus backbone
Correct answer: Houses end-user equipment such as servers and storage devices
The Equipment Distribution Area (EDA) is the zone where end-user equipment such as servers, storage, and network devices are located and connected.
Question 6: Which fiber optic connector type is most commonly recommended for high-density data centre applications due to its small form factor?
- LC duplex (Correct answer)
- SC duplex
- ST bayonet
- FC threaded
Correct answer: LC duplex
The LC (Lucent Connector) duplex connector is the industry standard for high-density data centre applications because its 1.25mm ferrule allows twice the port density of SC connectors.
Question 7: When using pre-terminated fiber trunk cables in a data centre, what is the primary advantage over field-terminated cables?
- Faster deployment with factory-tested and guaranteed insertion loss (Correct answer)
- Lower material cost per meter of cable
- Greater flexibility to customize lengths on-site
- Higher resistance to physical damage during installation
Correct answer: Faster deployment with factory-tested and guaranteed insertion loss
Pre-terminated trunk cables are factory-assembled and tested, ensuring consistent insertion loss values and enabling faster moves, adds, and changes compared to field termination.
CDCP Structured Cabling and Standards 4
What is the maximum pulling tension allowed for a 4-pair UTP cable during installation?